Phishing attempts in July broke all previous records with 19.2 million emails sent, a 16 per cent monthly increase, according to email security vendor Postini.
The company recorded 16.6 million phishing emails last month, the second highest level ever recorded.
"Phishing scams have been growing in number and sophistication," said Andrew Lochart, senior director of marketing at Postini.
He recommended companies to ensure that such mails are stopped at the network gateway rather than allowing them to spread further.
In contrast to increased levels of phishing, the number of virus infected messages for July decreased by 20 per cent compared to the previous month. This was the second consecutive month that the number of virus infected messages fell.
Postini's systems recorded more than 23 million directory harvest attacks, an eight per cent decrease compared to June's 25 million.
Spam rates remained stable, representing 88 per cent of total email messages sent.
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